Which term describes a pure substance that is made up of only one type of atom?

1)matter
2)rock
3)compound
4)element

ELEMENT

A pure substance is one that is composed of only one type of material.

This material may not necessarily be made from only one type of element, but can be composed from different elements yet be pure. An example of this is water. Water is made up of oxygen and hydrogen. Water that is free of contamination is termed as pure.

Examples of pure substances are:

1.Gold

2. Iron

3. Carbon

4. Sugar

5. Nitrogen gas

6. Oxygen gas

7. Salt

meiosis is the first to occur after the nuclei of opposite of opposite mating types fuse

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.